A method, apparatus and a system for thermally-assisted pulsed electromagnetic field stimulation for treatment of osteoarthritis are disclosed. In one embodiment, the system comprises a multi-coil applicator adapted for positioning near or around of the treated joint, a pulse generator functionally coupled to the applicator, a power supply, and a feedback loop for stabilizing the temperature of the joint. The feedback loop includes a heating element, a temperature sensor and an electronic controller for maintaining the temperature of the joint in the range of 38 to 42 degree C. At elevated temperatures the healing effect of PEMF stimulation on the cartilage is maximized and overall efficiency of the treatment is improved. To produce a high electric field, the coils of the applicator are made with a low number of turns, for example less than 5 turns, and are spatially arranged to cover the whole joint without “dead” zones.